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Mar 13, 2019 Owing to its varying behaviour when loaded by structures, [ [EN1997-1:2009]] classifies the subsoil into undisturbed and disturbed soil (subsequently altogether called soil) as well as rock (solid rock). In practice, however, a distinction between undisturbed and disturbed soil is not made. Consequently, all loose material is covered by the collective term “soil”, whereas all solid material is called “rock”. The different types of soil are to be...… |
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Mar 13, 2019 The following slides will look at soil characteristics in greater detail. |
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Mar 13, 2019 Soil is called backfill, if “it has been artificially placed”. Backfill is divided into:
[ [DIN1054:2010]], [EN1997-1:2009] (Image: Compacted backfill under a motorway) Most of the areas below the surface of traffic ways and … |
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Mar 13, 2019 The following categories will be used for a more detailed description: (Image: Unconsolidated soil categories) |
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Mar 13, 2019 The main types of soil are:
[[EN ISO 14688:2002]] differentiates
These main soil types consists of
which are likewise differentiated using particle fractions. |
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Mar 13, 2019 By non-cohesive soil, the individual mineral or rock grains form a loose cluster as a result of frictional forces that occur when the grain surfaces rub against each other. The characteristics of non-cohesive soil are influenced by the following parameters:
(Image: Non-cohesive soil particles, held loosely together through the grain surface friction) Sands, gravels, stones and their … |
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Mar 13, 2019 In the case of cohesive soil, the particles cling together as a result of electrostatic surface forces, and thus form a bonded and mouldable mass. Its characteristics (strength) is essentially influenced by the following parameters:
This type of soil is sensitive to weather conditions. it includes clays, clayey silts (e.g. sandy clay, sandy silt, loam, marl) as well as their mixtures with non-cohesive … |
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Mar 13, 2019 The soil is classified as organic soil according to DIN 1054 if the soil includes digested sludge and mineral (inorganic) soils with organic admixtures of animal or plant origin. The admixtures have to have a proportion by weight of more than 3 % or rather 5 % [ [DIN1054:2010]]. Examples of organic soil include humus sand, digested sludge, peat-containing sand, organic silt or clay. Depending on its degree of decomposition, organic soil has a fibrous, … |
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Mar 13, 2019 The (top) soil in a narrow sense is defined as the most biologically active part of the top crust of the earth, which is surrpunded by rock or soil below, and by vegetation or atmosphere above [MURL1991]. The soil can be classified, based on its percent by mass, into organic soil and mineral soil with an organic percentage [ [DINENISO14688:2018]]. (Image: Topsoil) (Table: Classification of soil with organic percentages according to EN ISO 14688-2) |
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Mar 13, 2019 According to [ [DINENISO14688-1:2011]], volcanic soil is defined as “magma that has been emitted into the atmosphere during intense volcanic eruptions and, over time has formed deposits; e.g. pumice, scoria, ash”. The main percentages of volcanic soils are designated and described according to their particle size, structure and colour. (Table: Designation and description of volcanic types of soil [ENISO14688]) |
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Mar 13, 2019 The grain particle shape has an influence on the texture and isotropy of the soil, as well as on the structural characteristics of the subsoil, such as the frictional resistance, shear strength, water permeability, compactness- and displacement capability [Soos96] [Trian00]. (Image: Particle shape - well rounded) (Image: Particle shape - Rounded) (Image: Particle shape - Sub rounded) (Image: Particle shape - Angular) (Image: Particle shape - Very … |
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Mar 13, 2019 The primary distinctive feature of mineral soil is the grain size of the individual particles. The determination of the grain size is the first step in the designation- and classification process of a certain type of soil. (Image: Soil grain sizes from 0 – 4 mm) (Image: Soil grain sizes from 4 – 25 mm) |
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Mar 13, 2019 An important factor in soil classification presented in the upcoming pages is the soil particle size (grain size). Two scales are used for classification purposes of soil grain size: the US Sieve Series and the Tyler Equivalent. The table below presents the most common sieve mesh opening sizes for these two scales is presented in the table below. (Table: US sieve mesh size) |
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Mar 13, 2019 The cumulative frequency polygon of the mass percentages of the given soil sample is called a grading curve (or grain size curve), and is used for a definite designation of the soil. (Image: Grading curves of some characteristic types of soil [Neuma64]) |
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Mar 13, 2019 (Image: Grain sizes classification) (Table: Soil characteristics) |
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Mar 13, 2019 Example: The measured values of the sedimentation analysis resulted in the following mass percentages: (Formula: Aus den Messwerten der Siebanalyse folgten die Gewichtsanteile) With ∑m (D < d) as the percent passing (percentage by weight) through the screen with the mesh size d and ∑ m(D) as the total mass of the sample. Consequently: (Formula: Gewichtsanteil y(0,063)) (Formula: Gewichtsanteil y(0,125)) (Formula: Gewichtsanteil y(0,25)) Table: Dry screening … |
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